FIELD: electrical engineering.
SUBSTANCE: emergency protection device contains a block for galvanic isolation and pre-scaling of input current and voltage signals, consisting of measuring current and voltage transformers, modules for setting control reference signals on current and voltage based on phase-lock-loop frequency control (PLL) circuits, modules of digital frequency filters of the main current and voltage harmonic, a block for determination of current and predicted electrical parameters of controlled current and voltage signals, a block for making a decision on emergency shutdown of the protected object. In addition, a block for determination of amplitude values of predicted current and voltage functions is introduced, inputs of which are connected to the block for determination of current and predicted electrical parameters of controlled current and voltage signals, and outputs are connected to modules for comparison of amplitude values of predicted current and voltage functions with setpoint values in the block for making a decision on emergency shutdown of the protected object.
EFFECT: increase in selectivity and reliability of detection of emergency and near-emergency modes of a traction power supply system of alternating current at early stages of their generation.
1 cl, 2 dwg
